More important is that Apple's app platform is still far ahead of its competition. And we think it's doing its real job, too: Helping Apple sell more iPhones and iPod touches, which are worth much, much more to Apple's top and bottom lines.

How'd we get $50 million to $100 million?

Apple has told the WSJ that "most" iPhone downloads are free apps. We don't know how many those are, so let's assume they're about two-thirds of the downloads.

That suggests that 100 million downloads (of 300 million) were paid apps.

Apple recently published the top 10 most-downloaded paid apps. Their average price is about $2.80. We'll round that up to $3.

That suggests Apple's gross revenue from paid apps is $300 million.

Apple takes a 30% cut, and gives 70% to developers. That's $90 million for Apple, which we'll round up to $100 million for simplicity's sake.

But this may be overstate the reality. In August, Steve Jobs told the WSJ that Apple made $30 million in gross sales for the first 60 million app downloads. Five times that (300 million downloads at that same rate) is $150 million, of which Apple would get 30%, or $45 million. We'll round that up to $50 million.